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Hydrogen–deuterium exchange (also called H–D or H/D exchange) is a chemical reaction in which a covalently bonded hydrogen atom is replaced by a deuterium atom, or vice versa. It can be applied most easily to exchangeable protons and deuterons, where such a transformation occurs in the presence of a suitable deuterium source, without any ...
Almost all the organic hydrogen is exchangeable to some extent. Isotopic exchange of organic hydrogen will reorder the distribution of deuterium and often incorporate external hydrogen. Generally, more mature materials are more heavily exchanged. With effective exchange, aliphatic hydrogen can finally reach isotopic equilibrium at the final stage.
Deuterium (hydrogen-2, symbol 2 H or D, also known as heavy hydrogen) ... Six plants, of which five are in operation, are based on D–H exchange in ammonia gas.
The authors found that a planet’s deuterium-hydrogen (DH) value would decrease about 16 parts per million in 170 million years when compared to the surrounding interstellar medium. If a planet ...
Semiheavy water, HDO, exists whenever there is water with light hydrogen (protium, 1 H) and deuterium (D or 2 H) in the mix. This is because hydrogen atoms (1 H and 2 H) are rapidly exchanged between water molecules. Water containing 50% 1 H and 50% 2 H in its hydrogen, is actually about 50% HDO and 25% each of H 2 O and D 2 O, in dynamic ...
Upon adding phenol to deuterated water (water containing D 2 O in addition to the usual H 2 O), a hydrogen-deuterium exchange is observed to affect phenol's hydroxyl group (resulting in C 6 H 5 OD), indicating that phenol readily undergoes hydrogen-exchange reactions with water. Mainly the hydroxyl group is affected—without a catalyst, the ...
The Shilov system was discovered by Alexander E. Shilov in 1969-1972 while investigating H/D exchange between isotopologues of CH 4 and H 2 O catalyzed simple transition metal coordination complexes. The Shilov cycle is the partial oxidation of a hydrocarbon to an alcohol or alcohol precursor (RCl) catalyzed by Pt II Cl 2 in an aqueous solution ...
NMR spectroscopy is nucleus specific. Thus, it can distinguish between hydrogen and deuterium. The amide protons in the protein exchange readily with the solvent, and, if the solvent contains a different isotope, typically deuterium, the reaction can be monitored by NMR spectroscopy. How rapidly a given amide exchanges reflects its solvent ...